Study background: Acquired immunodeficiency syndrome (AIDS) is a severe disease of immune system caused by Human Immunodeficiency Virus (HIV). Zidovudine (AZT) is an effective antiretroviral drug against HIV. Due to its poor bioavailability (50-60%) and short elimination half life (0.5-3 h), frequent administration of zidovudine is required resulting into dose dependent hematological toxicity. In the present study, an attempt was made to develop sustained release formulation of AZT employing the poly (propyl ether imine) (PETIM) dendrimer as a carrier. Methods:The AZT-dendrimer complex was prepared and studied by Fourier transform infrared (FTIR) analysis and nuclear magnetic resonance (NMR) spectroscopy. The entrapment efficiency and in-vitro drug release studies were conducted by dialysis bag method. Hemolytic toxicity, pharmacokinetic and biodistribution studies were performed to evaluate the biosafety and sustained release characteristic of prepared formulation. Results and Conclusion:The cumulative amount of zidovudine released in 1 h from the AZT-dendrimer formulation was 6.5 ± 0.3 % compared with 95.8 ± 4.1% from the control drug solution. Zidovudine release was prolonged upto 14 h with zidovudine-dendrimer complex (94.3 ± 3.8%). The findings of present investigation illustrated that PETIM dendrimer effectively encapsulate AZT, and can be used as a biosafe carrier for sustained delivery of zidovudine.